How to rename a dialogUser

Hello Pro's,

We have a need to rename a dialoguser. Are you aware of how we can do this? When we go into designer / permissions / system user it shows the username field un-editable. I went into object browser and see that field is “CanEdit =  false”. Does anyone have any suggestions or ways to have this changed? I was thinking of direct update into SQL but don’t want to mess anything up. My other thought was to just delete then recreate the user but don't want to lose any saved queries or settings.

Thank you,

Lu